Gastrodia-based filling and preparation method thereof

Abstract

The application discloses a gastrodia elata-based stuffing and a preparation method thereof, and belongs to the technical field of food, wherein the gastrodia elata-based stuffing comprises, by weight, 3-5 parts of gastrodia elata fermentation freeze-dried powder, 70-80 parts of instant oatmeal, 55-65 parts of isomaltooligosaccharide solution, 25-35 parts of xylitol, 15-25 parts of cooked cake powder, 80-100 parts of pitted red dates, 20-40 parts of low-sugar red date jam, 10-20 parts of salad oil, 1.0-2.0 parts of sodium alginate, 1.0-2.0 parts of an antioxidant, and 0.1-1.5 parts of an acid-base regulator. The gastrodia elata fermentation freeze-dried powder is prepared from fresh gastrodia elata through lactic acid bacteria fermentation and vacuum freeze drying. The application effectively removes the urine odor and fishy smell of gastrodia elata through lactic acid bacteria fermentation, maximally retains heat-sensitive active ingredients such as gastrodia elata elements by combining the vacuum freeze drying technology, and compounds the oatmeal, red dates, isomaltooligosaccharide solution and xylitol to build a unique flavor and texture system. The obtained stuffing is low in sugar, has a coordinated flavor, a delicate taste and good formability.

Description

Technical Field

[0001] This invention relates to the field of food technology, specifically to a gastrodia elata-based filling and its preparation method. Background Technology

[0002] As a core component of Chinese pastries, baked goods, and steamed foods, the quality of fillings directly determines the sensory experience and nutritional value of the final product. Traditional fillings (such as red bean paste, lotus seed paste, and mixed nuts) typically use extremely high levels of sucrose and fats (such as white sugar and lard) as their main base, making them typical high-sugar, high-fat food components. Long-term consumption of such fillings can easily lead to metabolic health problems such as obesity and high blood lipids, and also does not comply with the dietary restrictions for diabetic patients.

[0003] Faced with the trend of health-conscious consumption upgrading, although the market has launched low-sugar filling products, most rely on sugar alcohols as a simple substitute for sucrose, generally suffering from defects such as dry taste and monotonous flavor, failing to meet consumers' dual expectations of deliciousness and health. Meanwhile, with the promotion of the national concept of food and medicine homology and the updating of related catalogs, Gastrodia elata, as a food and medicine homology material with significant sedative and tranquilizing effects, provides new ideas for the development of functional health fillings. However, the application of Gastrodia elata in filling systems faces three major core technological bottlenecks: First, fresh or dried Gastrodia elata has a strong "horse urine smell" and earthy smell. Adding it directly will seriously damage the flavor base of the filling and produce an unpleasant odor that is difficult to mask, resulting in extremely poor sensory acceptability of the filling.

[0004] Secondly, active ingredients such as gastrodin are extremely sensitive to heat. They are easily decomposed and deactivated under high-temperature processing conditions (usually reaching 120℃~150℃) during the frying and concentration of fillings and under secondary heating conditions during subsequent applications, resulting in a significant loss of their functional value.

[0005] Third, the fibers of Gastrodia elata are coarse and dense. Adding it directly without processing will destroy the delicate taste and shaping characteristics of the filling, resulting in a dry, hard, sticky filling or poor structural stability, which seriously affects the processing adaptability and eating quality.

[0006] Furthermore, existing research on the application of Gastrodia elata in fillings is still in its early stages. Most attempts have only adopted a crude process of simple steaming, boiling, and direct mixing after crushing, which has failed to systematically solve the problem of synergistic regulation of flavor removal, activity retention and texture improvement, and has not yet formed a stable filling preparation process system suitable for industrial production.

[0007] Therefore, further improvements are necessary. Summary of the Invention

[0008] This invention aims to provide a low-sugar, odorless, high-retention-of-active-ingredients, excellent-texture, and well-balanced-flavor Gastrodia elata-based filling and its preparation method. This invention solves the technical problems of poor flavor, easy destruction of active ingredients, and undesirable texture when Gastrodia elata is used in baked goods.

[0009] A gastrodia elata-based filling designed for this purpose, comprising, by weight: 3-5 parts of Gastrodia elata fermented freeze-dried powder, 70-80 parts of instant oatmeal, 55-65 parts of isomaltooligosaccharide syrup, 25-35 parts of xylitol, 15-25 parts of cooked cake flour, 80-100 parts of pitted red dates, 20-40 parts of low-sugar red date jam, 10-20 parts of salad oil, 1.0-2.0 parts of sodium alginate, 1.0-2.0 parts of antioxidant, and 0.1-1.5 parts of acid-base regulator; The fermented freeze-dried powder of Gastrodia elata is obtained by fermenting fresh Gastrodia elata with Lactobacillus acidophilus and then freeze-drying it under vacuum.

[0010] The fermented freeze-dried Gastrodia elata powder is prepared by the following method: fresh Gastrodia elata is washed, peeled, and cut into 3-5 mm thin slices. It is then homogenized with an equal weight of water, sterilized at 121 degrees Celsius for 15 minutes, inoculated with 1.5%-2.5% of its weight of Lactobacillus acidophilus fermentation broth, and fermented at 28-32 degrees Celsius for 2-4 days to obtain fermented Gastrodia elata slurry. The fermented Gastrodia elata slurry is pre-frozen at -20 degrees Celsius to -25 degrees Celsius for 20-28 hours, then freeze-dried under vacuum for 40-56 hours, and pulverized through an 80-120 mesh sieve to obtain the final product. The weight ratio of the instant oatmeal to the gastrodia elata fermented freeze-dried powder is (14-27):1; The weight ratio of the isomaltooligosaccharide solution to xylitol is (1.5-2.5):1.

[0011] By weight, it includes: 3 parts of Gastrodia elata fermented freeze-dried powder, 80 parts of instant oatmeal, 65 parts of isomaltooligosaccharide syrup, 30 parts of xylitol, 20 parts of cooked rice flour, 90 parts of pitted red dates, 30 parts of low-sugar red date jam, 16 parts of salad oil, 1.6 parts of sodium alginate, 1.5 parts of vitamin C, and 1.2 parts of baking soda.

[0012] A method for preparing a gastrodia elata-based filling, comprising the above-mentioned gastrodia elata-based filling, wherein the preparation method includes the following steps: (1) Pretreatment of Gastrodia elata: Wash, peel and slice fresh Gastrodia elata, homogenize with water at a weight ratio of 1:1, autoclave at 121 degrees Celsius for 15 minutes, inoculate with Lactobacillus acidophilus fermentation broth, and ferment at 28-32℃ for 2-4 days to obtain fermented Gastrodia elata pulp; (2) Freeze-drying powder: After pre-freezing the fermented Gastrodia elata pulp, vacuum freeze-dry it, pulverize it and sieve it to obtain Gastrodia elata fermented freeze-dried powder; (3) Rehydration preparation: Rehydrate the fermented freeze-dried Gastrodia elata powder with warm water at a weight ratio of 1:2.5-1:3.5, add antioxidants and acid-base regulators, stir evenly to obtain rehydrated Gastrodia elata slurry; (4) Red date and oat processing: Steam pitted red dates with water until cooked, mix with instant oat flakes and grind to obtain red date and oat powder; (5) Mixing: Mix the rehydrated Gastrodia elata syrup, jujube and oat flour, isomaltooligosaccharide solution, xylitol, jujube jam, salad oil and sodium alginate evenly to obtain a mixed slurry; (6) Conditioning and shaping: Add cooked rice flour to the mixed slurry and stir until the filling forms a ball and has a moderate viscosity to obtain the Gastrodia elata-based filling.

[0013] The fermentation broth mentioned in step (1) is prepared by adding Lactobacillus acidophilus powder to sterile water, and the bacterial concentration is (2.5-3.5)×10⁻⁶. 8 CFU / mL, inoculation amount is 2% of the weight of Gastrodia elata pulp; The pre-freezing temperature in step (2) is -20℃ to -25℃, the pre-freezing time is 20-28h, the vacuum freeze-drying time is 40-56h, and the sieve mesh size is 80-120 mesh; The rehydration ratio in step (3) is 1:3, and the warm water temperature is 30-40℃.

[0014] In step (4), the amount of water added to the red dates is 30%-40% of the weight of the red dates, and they are steamed until the water is absorbed. The mixture described in step (5) is stirred for 15-25 minutes at a speed of 80-120 rpm; The conditioning process described in step (6) involves stirring for 5-10 minutes at a speed of 60-100 rpm.

[0015] Includes the following steps: (1) Pretreatment of Gastrodia elata: Wash fresh Gastrodia elata, peel it, cut it into 3-5 mm thin slices, and homogenize it with an equal weight of water until there are no obvious particles; autoclave at 121 degrees Celsius for 15 min, and prepare fermentation broth: add 0.3 g of Lactobacillus acidophilus powder with a viable count of 10 billion CFU / g to 50-80 mL of sterile water, shake to dissolve, and make up to 100 mL; pour the Gastrodia elata slurry into a sterile fermentation tank, inoculate it with 2% of its weight of fermentation broth, and ferment at 30℃ for 3 days; (2) Freeze-drying powder: Pour the fermented Gastrodia elata pulp into a freeze-drying pan, pre-freeze at -20℃ for 24 hours, freeze-dry under vacuum for 48 hours, grind into powder and pass through a 100-mesh sieve; (3) Rehydration preparation: Rehydrate the fermented freeze-dried Gastrodia elata powder with 35℃ warm water at a ratio of 1:3, add 1.5 parts vitamin C and 1.2 parts baking soda, and stir well; (4) Red date and oat processing: Steam 90 pitted red dates with 30mL of water until cooked, and then grind them together with 80 portions of instant oatmeal. (5) Mixing: Mix the rehydrated gastrodia elata pulp, red date and oat flour, 65 parts of isomaltooligosaccharide solution, 30 parts of xylitol, 30 parts of low-sugar red date jam, 16 parts of salad oil, and 1.6 parts of sodium alginate at 100 rpm for 20 min. (6) Conditioning and shaping: Add 20 parts of cooked cake flour and stir at 80 rpm for 8 minutes until the filling forms a ball and has a moderate viscosity.

[0016] The present invention, through the improvement of the above-described structure, has the following advantages compared with the prior art: 1. Significantly removes unpleasant flavors from Gastrodia elata: Through fermentation with Lactobacillus acidophilus, substances that produce the "horse urine odor" and earthy smell in fresh Gastrodia elata are effectively decomposed, solving the problem of unacceptable flavor when Gastrodia elata is added directly, thus making the overall flavor of the filling harmonious.

[0017] 2. Highly efficient preservation of active ingredients in Gastrodia elata: Vacuum freeze-drying is used instead of high-temperature drying or stir-frying, which avoids the decomposition of heat-sensitive functional components such as gastrodin during traditional high-temperature processing, thus ensuring the sedative and tranquilizing effects of Gastrodia elata as both food and medicine.

[0018] 3. Improve the texture and taste of the filling: Fermentation and freeze-drying processes destroy the coarse fiber structure of Gastrodia elata, making it easier to blend with other materials after rehydration; combined with ingredients such as instant oatmeal, cooked rice flour, and sodium alginate, the filling is delicate, non-sticky, and has good shape retention, making it less likely to collapse during baking.

[0019] 4. Achieving low-sugar and healthy properties: Replacing traditional sucrose with isomaltooligosaccharide syrup and xylitol significantly reduces the glycemic index of the filling, making it suitable for people who control their blood sugar and diabetic patients. At the same time, it avoids the dryness and poor aftertaste caused by single sugar alcohols.

[0020] 5. Synergistic enhancement of antioxidants and stability: The addition of antioxidants and pH regulators, combined with the natural antioxidants in the fermented products of Gastrodia elata, can inhibit the oxidative deterioration of the filling during storage and baking, and extend the shelf life of the product.

[0021] 6. Providing unique nutritional and flavor layers: Pitted red dates provide natural sweetness and fruity aroma, instant oatmeal increases dietary fiber and satiety, and fermented gastrodia elata products bring a light fermented flavor. These three, combined with sugar alcohols, oils, etc., form a complex flavor system that is low in sugar, high in fiber, and has the characteristics of being both food and medicine. Detailed Implementation

[0022] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described in detail below. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0023] This Gastrodia elata-based filling, by weight, includes: 3-5 parts of Gastrodia elata fermented freeze-dried powder, which is the core innovation of this invention, is not a simple mixture of raw materials, but a functional raw material processed by a specific process. Its effects are: 1. It provides active ingredients such as gastrodin, giving the filling a calming and soothing health value; 2. After fermentation and freeze-drying, it has no "horse urine smell" or earthy smell, and has a light fermented aroma; 3. The freeze-dried powder has a porous structure and good rehydration properties, forming a delicate paste without compromising the delicate texture of the filling.

[0024] 70-80 servings of instant oatmeal, used as the main textural filler, have the following effects: 1. The β-glucan it contains has strong water-holding and gelling properties, forming a gel network that replaces the textural support role of sucrose and prevents the filling from falling apart; 2. It increases soluble dietary fiber and enhances health properties; 3. It provides the aroma of grains, which, together with the aroma of dates and fermentation, forms a complex aroma.

[0025] The combination of 55-65 parts isomaltooligosaccharide syrup and 25-35 parts xylitol forms a low-sugar sweetness system. Their synergistic effects are: 1. The sweetness curve after blending is closer to sucrose, resulting in a smooth taste and avoiding the dryness and bitter aftertaste of single sugar alcohols; 2. Isomaltooligosaccharide syrup provides viscosity and moisture retention, while xylitol has strong hygroscopic properties, together keeping the filling soft and preventing it from becoming grainy; 3. Isomaltooligosaccharide is a prebiotic, and xylitol does not raise blood sugar, making the filling suitable for diabetics and people controlling their blood sugar.

[0026] 15-25 parts of cooked rice flour, as a viscosity regulator and forming agent, have the following effects: 1. After the amylopectin gelatinizes, it produces stickiness, which makes loose materials clump together and form a shape; 2. It adjusts the surface viscosity of the filling, making it "clump together without sticking to the hands", which is convenient for industrial packaging; 3. It works synergistically with sodium alginate to prevent collapse during baking.

[0027] 80-100 portions of pitted red dates serve as a natural flavoring and sweetener, with the following effects: 1. Providing a rich date aroma, effectively masking any slight off-flavors that may remain from fermented gastrodia elata; 2. Providing natural fructose and glucose, making the sweetness more natural; 3. The pectin and fiber they contain further optimize the texture of the filling.

[0028] 20-40 servings of low-sugar jujube jam can enhance the jujube flavor, further masking any slight off-flavors that may remain from fermented gastrodia elata.

[0029] 10-20 parts salad oil, as a lubricant, has the following effects: 1. Coating the filling particles, reducing friction, and making the texture smooth and non-sticky; 3. Forming an oil film on the surface to prevent sticking; 4. Providing a moist feel and compensating for the dryness that may result from a low-sugar formula.

[0030] Sodium alginate, at 1.0-2.0 parts, acts as a thickener and stabilizer, with the following effects: 1. It dissolves in water to form a high-viscosity solution, increasing the consistency of the filling; 2. It forms an irreversible thermal gel with calcium ions in the filling, significantly enhancing the heat resistance and shape retention of the filling; 3. As dietary fiber, it strengthens health functions.

[0031] Antioxidant 1.0-2.0 parts, as an active protectant, has the following effects: 1. It preferentially reacts with oxygen, protecting phenolic active ingredients such as gastrodin from oxidation; 2. It inhibits oil oxidation and extends product shelf life; 3. It inhibits enzymatic browning and maintains the color of the filling.

[0032] The pH adjuster is 0.1-1.5 parts. As a pH adjuster, its effects are: 1. Neutralizing the acidity (pH 4.0-4.5) of fermented gastrodia elata paste to near neutral (pH 5.5-6.5), preventing the filling from being too acidic and affecting the taste; 2. Optimizing the flavor, making the fermented aroma and jujube sweetness more prominent; 3. Producing a small amount of gas makes the filling slightly fluffy and improves its firmness.

[0033] Among them, the fermented freeze-dried powder of Gastrodia elata is made from fresh Gastrodia elata through fermentation with Lactobacillus acidophilus and vacuum freeze-drying.

[0034] Gastrodia elata fermented freeze-dried powder is prepared by the following method: Fresh Gastrodia elata is washed, peeled, and cut into 3-5 mm thin slices. It is homogenized with an equal weight of water, sterilized at 121 degrees Celsius for 15 minutes, inoculated with 1.5%-2.5% of its weight of Lactobacillus acidophilus fermentation broth, and fermented at 28-32 degrees Celsius for 2-4 days to obtain fermented Gastrodia elata slurry. The fermented Gastrodia elata slurry is pre-frozen at -20 degrees Celsius to -25 degrees Celsius for 20-28 hours, then freeze-dried under vacuum for 40-56 hours, and pulverized through an 80-120 mesh sieve to obtain the final product.

[0035] The process of washing, peeling, and slicing fresh gastrodia elata into 3-5mm thin slices is to remove the source of odor and coarse fiber from the surface. The moderate thickness of the slices ensures efficient homogenization and uniform fermentation.

[0036] Homogenize the gastrodia elata pulp with an equal weight of water. The 1:1 water-to-material ratio ensures that the gastrodia elata pulp has a moderate consistency, providing a good growth and reproduction environment for Lactobacillus acidophilus and facilitating subsequent inoculation and mixing.

[0037] Autoclaving at 121°C for 15 minutes, followed by inoculation with 1.5%-2.5% by weight of Lactobacillus acidophilus fermentation broth, and fermentation at 28-32°C for 2-4 days: This is the core step in solving the off-odor problem of Gastrodia elata. Its working principle is: during its growth and metabolism, Lactobacillus acidophilus secretes extracellular enzymes such as proteases and lipases to decompose the proteins and fat precursors that produce the off-odor in Gastrodia elata, and metabolizes odor-causing substances such as aldehydes, ketones, and sulfur-containing compounds as carbon / nitrogen sources. The technical effects are: 1. Effectively removes the "horse urine odor" and earthy smell under a mild 30°C environment; 2. The fermentation temperature is far lower than the decomposition temperature of gastrodin, thus avoiding high-temperature degradation; 3. The organic acids and esters produced during fermentation give Gastrodia elata a new, delicate fermented aroma.

[0038] Pre-freezing at -20℃ to -25℃ for 20-28 hours is a rapid freezing process that causes water to form tiny ice crystals, avoiding damage to cell structure and protecting the organelles containing gastrodin, thus laying the foundation for subsequent freeze-drying.

[0039] Vacuum freeze-drying for 40-56 hours is the core step in protecting the activity of gastrodin. Its working principle is as follows: under vacuum, ice crystals in the frozen material directly sublimate into water vapor and are removed, keeping the material at a consistently low temperature. The technical benefits are: 1. Low temperature throughout the process (material temperature ≤ 0℃), completely avoiding thermal degradation of heat-sensitive gastrodin; 2. The vacuum environment isolates oxygen, reducing the oxidative loss of gastrodin. Compared to hot air drying at 60-80℃, the gastrodin retention rate can be increased by 15%-20%.

[0040] The powder is pulverized through an 80-120 mesh sieve to obtain a uniform powder with a particle size of about 150μm, which facilitates accurate weighing and uniform mixing with other powders, ensuring that the filling has a delicate texture without any grainy feel.

[0041] The weight ratio of instant oatmeal to freeze-dried fermented Gastrodia elata powder is (14-27):1. This limits the maximum amount of Gastrodia elata used. If the proportion of Gastrodia elata is too high (ratio <14), it will disrupt the flavor balance and result in an overly strong fermented taste; if the proportion is too low (ratio >27), the functional components will be insufficient. This range ensures that while obtaining sufficient active ingredients from Gastrodia elata, its flavor can be perfectly harmonized and masked by oatmeal and red dates.

[0042] The weight ratio of isomaltooligosaccharide syrup to xylitol is (1.5-2.5):1. This optimizes the formulation of the low-sugar sweetness system. At this ratio, the sweetness, viscosity, moisture retention, and anti-crystallization properties of the mixed syrup are optimally balanced, resulting in a taste closest to traditional sucrose fillings and effectively preventing the fillings from "crystallizing" during storage.

[0043] Specifically, the preferred Gastrodia elata-based filling in this embodiment, by weight, includes: 3 parts of Gastrodia elata fermented freeze-dried powder, 80 parts of instant oatmeal, 65 parts of isomaltooligosaccharide syrup, 30 parts of xylitol, 20 parts of cooked rice flour, 90 parts of pitted red dates, 30 parts of low-sugar red date jam, 16 parts of salad oil, 1.6 parts of sodium alginate, 1.5 parts of vitamin C, and 1.2 parts of baking soda.

[0044] This formulation was validated in Example 1. Testing showed it achieved the highest sensory score (81 points). The components exhibited the strongest synergistic effect at this ratio: the ratio of oat flakes to gastrodia elata powder was 26.7:1, falling within the preferred range, resulting in optimal flavor harmony; the ratio of isomaltooligosaccharide syrup to xylitol was approximately 2.17:1, also within the preferred range, providing optimal sweetness and moisturizing properties. Furthermore, the additional addition of "low-sugar jujube sauce" (30 parts) further enhanced the dominant jujube aroma, resulting in a richer and more complex flavor profile.

[0045] The preparation method of the above-mentioned Gastrodia elata-based filling includes the following steps: (1) Pretreatment of Gastrodia elata: Wash, peel and slice fresh Gastrodia elata, homogenize with water at a weight ratio of 1:1, autoclave at 121 degrees Celsius for 15 minutes, inoculate with Lactobacillus acidophilus fermentation broth, and ferment at 28-32℃ for 2-4 days to obtain fermented Gastrodia elata pulp; (2) Freeze-drying powder: After pre-freezing the fermented Gastrodia elata pulp, vacuum freeze-dry it, pulverize it and sieve it to obtain Gastrodia elata fermented freeze-dried powder; (3) Rehydration preparation: Rehydrate the fermented freeze-dried Gastrodia elata powder with warm water at a weight ratio of 1:2.5-1:3.5, add antioxidants and acid-base regulators, stir evenly to obtain rehydrated Gastrodia elata slurry; (4) Red date and oat processing: Steam pitted red dates with water until cooked, mix with instant oat flakes and grind to obtain red date and oat powder; (5) Mixing: Mix the rehydrated Gastrodia elata syrup, jujube and oat flour, isomaltooligosaccharide solution, xylitol, jujube jam, salad oil and sodium alginate evenly to obtain a mixed slurry; (6) Conditioning and shaping: Add cooked rice flour to the mixed slurry and stir until the filling forms a ball and has a moderate viscosity to obtain the Gastrodia elata-based filling.

[0046] Specifically, in the preferred step (1) of this embodiment, the fermentation broth is prepared by adding Lactobacillus acidophilus powder to sterile water, and the bacterial concentration is (2.5-3.5)×10⁻⁶. 8 CFU / mL, the inoculation amount is 2% of the weight of Gastrodia elata pulp.

[0047] In step (2), the pre-freezing temperature is -20℃ to -25℃, the pre-freezing time is 20-28h, the vacuum freeze-drying time is 40-56h, and the sieve mesh size is 80-120 mesh.

[0048] In step (3), the rehydration ratio is 1:3 and the warm water temperature is 30-40℃.

[0049] In step (4), the amount of water added to the red dates is 30%-40% of the weight of the red dates, and they are steamed until the water is absorbed.

[0050] In step (5), the mixture is stirred for 15-25 minutes at a speed of 80-120 rpm.

[0051] In step (6), the conditioning process involves stirring for 5-10 minutes at a speed of 60-100 rpm.

[0052] In step (1), the pretreatment of Gastrodia elata is the core of which is biological deodorization. By controlling the fermentation temperature and time, the odorous substances are completely transformed without destroying the active ingredients. This step replaces the traditional cumbersome steaming, blanching, and chemical deodorization, making the process simpler and the conditions milder.

[0053] Step (2) freeze-drying is the core of which is low-temperature activity preservation. The freeze-dried Gastrodia elata powder not only has high activity, but also good rehydration and storage stability, making it a standardized industrial raw material that can be used at any time.

[0054] Step (3) Rehydration and Preparation: The core of this step is functional activation and pre-protection. 1. Rehydration: Restore the freeze-dried powder to a state similar to a fresh slurry, making it easier to blend with other materials. A 1:3 ratio is preferred to obtain a slurry with optimal consistency. 2. Adding Vitamin C: Establishing an antioxidant environment at the initial stage of filling preparation, allowing it to continuously protect easily oxidized components such as gastrodin throughout the subsequent processes. 3. Adding Baking Soda: Uniformly adjusting the pH value in the liquid phase, neutralizing the acid produced during fermentation, creating the best environment for subsequent mixing, and optimizing the flavor of the final product.

[0055] Step (4) Red Date and Oat Processing: The core of this step is the pre-preparation of flavor and texture matrix. 1. Steaming the Red Dates: This softens the red dates, dissolves the pectin, gelatinizes the starch, and kills microorganisms. 2. Mixing and Grinding: Grind the red dates and oats together to allow the date and oat aromas to be evenly combined at the microscopic level, forming a synergistic flavor. The steamed red dates are sticky, and after being mixed and ground with the oat flakes, they form a preliminary gel network, laying the foundation for the overall texture in the subsequent steps.

[0056] Step (5) Mixing: The core of this step is system construction and emulsification. 1. Order of addition: First add the liquid phase of rehydrated Gastrodia elata syrup and sugar alcohol solution to facilitate the subsequent dispersion of powder. Sodium alginate is added last to avoid premature thickening and uneven mixing. 2. Stirring parameters: Stir at medium speed (100 rpm) for 20 minutes to ensure that each component is fully dispersed and emulsified to form a stable oil-in-water emulsion, while avoiding excessive shearing that could damage the gel structure of oat β-glucan and sodium alginate.

[0057] Step (6) Conditioning and Shaping: The core of this step is the final precise control of texture. 1. Add cooked rice flour last: Add cooked rice flour last as a "texture regulator". It can be finely adjusted according to the actual consistency of the mixed slurry to ensure the consistency of the final filling. 2. Gentle stirring: Stir at low speed (80 rpm) for a short time (8 min) to allow the cooked rice flour to fully absorb water and gelatinize, but avoid over-stirring which would cause the dough to "develop gluten" and harden. 3. Endpoint judgment: "Forming a ball and having moderate viscosity" are the key process control points for the filling. This ensures that the filling is easy to wrap (not sticky), can maintain its shape during baking (not collapse), and has a suitable taste when eaten (not sticky).

[0058] Furthermore, the high retention rate of gastrodin is demonstrated. To clearly illustrate the technical effects of this embodiment, the complete operation process and results of the preferred embodiment are presented again below to prove that the synergistic effect of all the above technical features can be achieved. Best Practice

[0059] Filling recipe: 3 parts Gastrodia elata fermented freeze-dried powder, 80 parts instant oatmeal, 65 parts isomaltooligosaccharide syrup, 30 parts xylitol, 20 parts cooked rice flour, 90 parts pitted red dates, 30 parts low-sugar red date jam, 16 parts salad oil, 1.6 parts sodium alginate, 1.5 parts vitamin C, and 1.2 parts baking soda.

[0060] Filling preparation method: (1) Pretreatment of Gastrodia elata: Take 100g of fresh Gastrodia elata, wash, peel, and cut into 3-5mm thin slices, add 100g of water to homogenize. Autoclave at 121°C for 15min, take 0.3g of 10 billion CFU / g Lactobacillus acidophilus powder, dissolve in 70mL of sterile water, and make up to 100mL. Take 4mL of this bacterial solution and inoculate it into 200g of Gastrodia elata slurry, and ferment at 30°C for 3 days; (2) Freeze-drying powder: Fermented slurry was pre-frozen at -20℃ for 24h, then freeze-dried under vacuum (cold trap -45℃, vacuum degree 5Pa) for 48h, and pulverized through a 100-mesh sieve to obtain about 10g of Gastrodia elata fermented freeze-dried powder; (3) Rehydration preparation: Take 3g of the above freeze-dried powder, add 9g of 35℃ warm water to rehydrate, then add 1.5g of vitamin C and 1.2g of baking soda, and stir well; (4) Red date and oat processing: Take 90g of pitted red dates, add 30g of water and steam until cooked, then grind them together with 80g of instant oat flakes. (5) Mixing: Mix the rehydrated slurry from step (3), the powder from step (4), 65g of isomaltooligosaccharide solution, 30g of xylitol, 30g of low-sugar jujube jam, 16g of salad oil, and 1.6g of sodium alginate, and stir at 100 rpm for 20 minutes. (6) Conditioning and shaping: Add 20g of cooked rice flour and stir at 80rpm for 8 minutes until the filling forms a ball and is no longer sticky.

[0061] In step (2), in addition to the pre-freezing and freeze-drying times, the key process parameters for vacuum freeze-drying also include the cold trap temperature (usually ≤-40℃) and the vacuum degree (usually ≤10Pa). These are necessary conditions for achieving ice crystal sublimation and preventing the material temperature from rising. Those skilled in the art can set these parameters according to the equipment to achieve the function of "vacuum freeze-drying".

[0062] The physicochemical and microbiological indicators of the Gastrodia elata-based filling prepared in the above-mentioned preferred embodiment were tested, and the results are as follows: Physicochemical indicators The total sugar (calculated as sucrose), reducing sugar, moisture, fat, protein, acid value (calculated as fat), and peroxide value (calculated as fat) of the Gastrodia elata-based filling were determined, and the results are shown in Table 1. The results show that the total sugar content of the Gastrodia elata-based filling is 25.20 g / 100g, significantly lower than the limit of ≤50 g / 100g in the General Rules for Mooncake Quality GB / T 19855-2023; the fat content is 7.14 g / 100g, far below the upper limit of ≤24 g / 100g in the standard, reflecting the product's low-sugar and low-fat formula. The moisture and protein contents are 13.17 g / 100g and 4.08 g / 100g, respectively, both meeting the physicochemical requirements for Cantonese-style mooncake fillings.

[0063] Acid value and peroxide value are key indicators reflecting the degree of oxidative rancidity of oils and fats, directly affecting the flavor and shelf life of products. In this test, the acid value was 0.27 g / 100 g (based on fat) and the peroxide value was 0.0031 g / 100 g (based on fat). Both were low, meeting the hygiene and safety requirements for food fillings, indicating that the degree of oil oxidation in the product was low and the quality was stable.

[0064] All of the above physicochemical indicators meet the requirements of GB / T 21270-2007 for food fillings, and the total sugar and fat content are significantly lower than the national standard, demonstrating the product characteristics of reduced sugar and low fat; the acid value and peroxide value are far below the safety limit, indicating that the product's oil quality is stable and its safety is good.

[0065] Table 1 below shows the physicochemical results of Gastrodia elata-based filling. Microbiological indicators According to the national standard methods of GB 4789.2-2022, GB 4789.3-2025, and GB 4789.15-2016, the total bacterial count of the Gastrodia elata-based filling was 1.3×10⁴ CFU / g, the coliform count was <3.0 CFU / g, the mold count was 75 CFU / g, and the yeast count was 10 CFU / g. This meets the hygiene requirements for pastry foods, meets the microbiological safety standards, and the production process is controllable, demonstrating the safety and feasibility for industrial production.

[0066] The above describes the preferred embodiments of the present invention, illustrating and describing the basic principles, main features, and advantages of the invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as defined by the appended claims and their equivalents.

Claims

1. A gastrodia elata-based filling, characterized in that, By weight, it includes: 3-5 parts of Gastrodia elata fermented freeze-dried powder, 70-80 parts of instant oatmeal, 55-65 parts of isomaltooligosaccharide syrup, 25-35 parts of xylitol, 15-25 parts of cooked cake flour, 80-100 parts of pitted red dates, 20-40 parts of low-sugar red date jam, 10-20 parts of salad oil, 1.0-2.0 parts of sodium alginate, 1.0-2.0 parts of antioxidant, and 0.1-1.5 parts of acid-base regulator; The fermented freeze-dried powder of Gastrodia elata is obtained by fermenting fresh Gastrodia elata with Lactobacillus acidophilus and then freeze-drying it under vacuum.

2. The Gastrodia elata-based filling according to claim 1, characterized in that, The fermented freeze-dried Gastrodia elata powder is prepared by the following method: fresh Gastrodia elata is washed, peeled, and cut into 3-5 mm thin slices. It is then homogenized with an equal weight of water, sterilized at 121 degrees Celsius for 15 minutes, inoculated with 1.5%-2.5% of its weight of Lactobacillus acidophilus fermentation broth, and fermented at 28-32 degrees Celsius for 2-4 days to obtain fermented Gastrodia elata slurry. The fermented Gastrodia elata slurry is pre-frozen at -20 degrees Celsius to -25 degrees Celsius for 20-28 hours, then freeze-dried under vacuum for 40-56 hours, and pulverized through an 80-120 mesh sieve to obtain the final product. The weight ratio of the instant oatmeal to the gastrodia elata fermented freeze-dried powder is (14-27):1; The weight ratio of the isomaltooligosaccharide solution to xylitol is (1.5-2.5):

1.

3. The Gastrodia elata-based filling according to claim 1 or 2, characterized in that, By weight, it includes: 3 parts of Gastrodia elata fermented freeze-dried powder, 80 parts of instant oatmeal, 65 parts of isomaltooligosaccharide syrup, 30 parts of xylitol, 20 parts of cooked rice flour, 90 parts of pitted red dates, 30 parts of low-sugar red date jam, 16 parts of salad oil, 1.6 parts of sodium alginate, 1.5 parts of vitamin C, and 1.2 parts of baking soda.

4. A method for preparing a gastrodia elata-based filling, characterized in that, The preparation method includes the Gastrodia elata-based filling according to any one of claims 1-3, wherein the preparation method includes the following steps: (1) Pretreatment of Gastrodia elata: Wash, peel and slice fresh Gastrodia elata, homogenize with water at a weight ratio of 1:1, autoclave at 121 degrees Celsius for 15 minutes, inoculate with Lactobacillus acidophilus fermentation broth, and ferment at 28-32℃ for 2-4 days to obtain fermented Gastrodia elata pulp; (2) Freeze-drying powder: After pre-freezing the fermented Gastrodia elata pulp, vacuum freeze-dry it, pulverize it and sieve it to obtain Gastrodia elata fermented freeze-dried powder; (3) Rehydration preparation: Rehydrate the fermented freeze-dried Gastrodia elata powder with warm water at a weight ratio of 1:2.5-1:3.5, add antioxidants and acid-base regulators, stir evenly to obtain rehydrated Gastrodia elata slurry; (4) Red date and oat processing: Steam pitted red dates with water until cooked, mix with instant oat flakes and grind to obtain red date and oat powder; (5) Mixing: Mix the rehydrated Gastrodia elata syrup, jujube and oat flour, isomaltooligosaccharide solution, xylitol, jujube jam, salad oil and sodium alginate evenly to obtain a mixed slurry; (6) Conditioning and shaping: Add cooked rice flour to the mixed slurry and stir until the filling forms a ball and has a moderate viscosity to obtain the Gastrodia elata-based filling.

5. The method for preparing the Gastrodia elata-based filling according to claim 4, characterized in that, The fermentation broth mentioned in step (1) is prepared by adding Lactobacillus acidophilus powder to sterile water, and the bacterial concentration is (2.5-3.5)×10⁻⁶. 8 CFU / mL, inoculation amount is 2% of the weight of Gastrodia elata pulp; The pre-freezing temperature in step (2) is -20℃ to -25℃, the pre-freezing time is 20-28h, the vacuum freeze-drying time is 40-56h, and the sieve mesh size is 80-120 mesh; The rehydration ratio in step (3) is 1:3, and the warm water temperature is 30-40℃.

6. The method for preparing the Gastrodia elata-based filling according to claim 5, characterized in that, In step (4), the amount of water added to the red dates is 30%-40% of the weight of the red dates, and they are steamed until the water is absorbed. The mixture described in step (5) is stirred for 15-25 minutes at a speed of 80-120 rpm; The conditioning process described in step (6) involves stirring for 5-10 minutes at a speed of 60-100 rpm.

7. The method for preparing the Gastrodia elata-based filling according to any one of claims 4-6, characterized in that, Includes the following steps: (1) Pretreatment of Gastrodia elata: Wash fresh Gastrodia elata, peel it, cut it into 3-5 mm thin slices, and homogenize it with an equal weight of water until there are no obvious particles; prepare fermentation liquid: autoclave at 121 degrees Celsius for 15 min, add 0.3 g of Lactobacillus acidophilus powder with a viable count of 10 billion CFU / g to 50-80 mL of sterile water, shake to dissolve, and make up to 100 mL; pour the Gastrodia elata slurry into a sterile fermentation tank, inoculate it with 2% of its weight of fermentation liquid, and ferment at 30℃ for 3 days; (2) Freeze-drying powder: Pour the fermented Gastrodia elata pulp into a freeze-drying pan, pre-freeze at -20℃ for 24 hours, freeze-dry under vacuum for 48 hours, grind into powder and pass through a 100-mesh sieve; (3) Rehydration preparation: Rehydrate the fermented freeze-dried Gastrodia elata powder with 35℃ warm water at a ratio of 1:3, add 1.5 parts vitamin C and 1.2 parts baking soda, and stir well; (4) Red date and oat processing: Steam 90 pitted red dates with 30mL of water until cooked, and then grind them together with 80 portions of instant oatmeal. (5) Mixing: Mix the rehydrated gastrodia elata pulp, red date and oat flour, 65 parts of isomaltooligosaccharide solution, 30 parts of xylitol, 30 parts of low-sugar red date jam, 16 parts of salad oil, and 1.6 parts of sodium alginate at 100 rpm for 20 min. (6) Conditioning and shaping: Add 20 parts of cooked cake flour and stir at 80 rpm for 8 minutes until the filling forms a ball and has a moderate viscosity.